#include<stdio.h>
#include<string.h>

int main(){
    char text[1000]="I love you very much ,do you know, okey?";
    char code[1000];
    int offset=3;

    int i,len=strlen(text);
    for(i=0; i<len; i++)
        if(isalpha(text[i]))        {
            if(isupper(text[i]))
                code[i]=(text[i]-'A'+offset)%26+'A';
            else
                code[i]=(text[i]-'a'+offset)%26+'a';
        }
        else
            code[i]=text[i];
    code[len]=0;
    puts(code);

    return 0;
}
